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MERSEN FUSE 250V 5ST 0,8A 5.20 MI5ST25V0,8
Mersen Q090542 MI5ST25V0.8 time-delay 5 x 20 mm glass cartridge fuse rated at 800 mA and 250 V AC for industrial equipment, power supplies and electrical circuit protection.
Why Choose the Mersen Q090542 5ST Miniature Fuse?
The Mersen Q090542, also identified by the catalogue reference MI5ST25V0.8, is a compact 5 x 20 mm time-delay glass cartridge fuse designed to provide dependable overcurrent protection for electrical equipment, industrial controls and electronic circuits. As part of the established Mersen 5ST IEC miniature fuse series, it withstands brief start-up currents while protecting connected equipment against sustained overloads and short circuits.
The Q090542 features a transparent glass body that allows straightforward visual inspection of the internal fuse element. Its standard cylindrical format provides compatibility with suitable 5 x 20 mm fuse holders and mounting clips, making it practical for original equipment manufacture, control-panel construction and routine maintenance replacement.
With a rated current of 800 mA and a rated voltage of 250 V AC, this fuse is suitable for circuits containing transformers, power supplies, control components and other equipment that may experience temporary inrush currents during normal start-up.
Key Advantages
- Reliable time-delay miniature fuse for electrical equipment protection.
- 800 mA current rating for accurately matched control circuits.
- 250 V AC voltage rating suitable for industrial and electronic applications.
- Withstands temporary start-up and inrush currents without unnecessary operation.
- Compact 5 x 20 mm cartridge format for space-efficient installation.
- Transparent glass body enables convenient visual inspection.
Key Features
- Mersen 5ST IEC miniature fuse series.
- Catalogue reference: MI5ST25V0.8.
- 800 mA rated current.
- 250 V AC rated voltage.
- Time-delay operating characteristic.
- Standard 5 x 20 mm cylindrical fuse size.
- Glass cartridge body for visual fuse-element inspection.
- Suitable for compatible fuse holders and mounting clips.
Dependable Protection for Circuits with Inrush Current
Time-delay fuses such as the Mersen Q090542 are designed to tolerate short-duration current surges that occur when transformers, power supplies and other electrical loads are energised. This helps prevent nuisance fuse operation during normal start-up while maintaining dependable protection against sustained overloads and short circuits.
The standard 5 x 20 mm format enables straightforward installation and replacement within compatible equipment. Its glass construction also allows engineers to inspect the fuse element visually when diagnosing electrical faults or carrying out routine maintenance.
Typical Applications
- Industrial control panels.
- Electronic power supplies.
- Transformers and inductive circuits.
- Automation and control equipment.
- Instrumentation and measuring devices.
- OEM machinery and electrical assemblies.
Technical Specifications
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| Current | 0.8 A | |
|---|---|---|
| Voltage | 250 V | |
| Device Type | Fuse link | |
| Fuse Type | Miniature | |
| Fuse Size | 5x20 mm | |
| Fuse Class | Time delay | |
| Manufacturer | Mersen | |
| Series | 5ST IEC Miniature Fuses | |
| Model | Q090542 | |
| Catalogue reference | MI5ST25V0.8 | |
| Product type | Miniature cartridge fuse | |
| Rated current | 800 mA | |
| Equivalent current | 0.8 A | |
| Rated voltage | 250 V AC | |
| Operating characteristic | Time delay | |
| Fuse speed designation | T | |
| Fuse size | 5 x 20 mm | |
| Overall length | 20 mm | |
| Nominal diameter | 5 mm | |
| Body material | Glass | |
| Mounting type | Fuse holder or clip mounting | |
| Typical protection | Electrical distribution circuits and industrial equipment |
Frequently Asked Questions
What is the Mersen Q090542 used for?
The Mersen Q090542 provides overcurrent and short-circuit protection for electrical equipment, industrial controls, power supplies and electronic circuits.
What is the current rating of the Q090542?
The fuse has a rated current of 800 mA, which is equivalent to 0.8 A.
What voltage is this fuse rated for?
The Mersen Q090542 is rated for operation at up to 250 V AC.
Is the Q090542 a fast-acting fuse?
No. It is a time-delay fuse designed to withstand brief inrush currents before operating during a sustained overload or short circuit.
What size is the Mersen Q090542?
The fuse has a standard cylindrical cartridge size of 5 x 20 mm for installation in a compatible fuse holder or mounting clip.
Trusted by Electrical Professionals Worldwide
Mersen miniature fuses are trusted by electrical engineers, panel builders and equipment manufacturers for dependable overcurrent protection, consistent operation and reliable performance in industrial electrical systems.
